Enabling general JavaScript in WebViewClient

While searching for an answer in google, it seems that I'm not the only one stuck with a problem that seems impossible to solve.

I've managed to create a WebView with a custom WebViewClient - this makes it possible for me to have a processdialog and show an error message if an URL couldn't be loaded.

But this creates a problem with JavaScript. The URL I'm loading has some JavaScript which changes some HTML elements CSS styles (showing or hiding element) or redirects to another location onclick - or maybe even want's to show an alert box. But by using the WebViewClient none of those are working.

This is how I load a page:

public void loadUrl(String url)
{
    final ProgressDialog dialog = ProgressDialog.show(myActivity.this, "",  getString(R.string.loading), true);
            final WebView myWebView = (WebView) findViewById(R.id.webview);
            myWebView.setVerticalScrollBarEnabled(false);
            myWebView.setHorizontalScrollBarEnabled(false);
            WebSettings webSettings = myWebView.getSettings();
            webSettings.setJavaScriptEnabled(true);                                         


            myWebView.setWebViewClient(new WebViewClient() 
            {
                @Override
                public boolean shouldOverrideUrlLoading(WebView view, String url) 
                {
                    Toast.makeText(myActivity.this, url, Toast.LENGTH_SHORT).show(); //Debugging purposes
                if (url.endsWith(".mp4")) 
                {
                        Intent intent = new Intent(Intent.ACTION_VIEW);
                        intent.setDataAndType(Uri.parse(url), "video/mp4");
                        view.getContext().startActivity(intent);  
                }
                else
                {                           
                        view.loadUrl(url);
                    }

                    return true;
                }

                public void onPageFinished(WebView view, String url) 
                {
                    //Toast.makeText(myActivity.this, "Oh no!", Toast.LENGTH_SHORT).show();
                    dialog.dismiss();
                }

                public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) 
                {
                    Toast.makeText(myActivity.this, description, Toast.LENGTH_SHORT).show();
                    String summary = "<html><body><strong>" + getString(R.string.lost_connection) + "</body></html>";
                    myWebView.loadData(summary, "text/html", "utf-8");   
                }              

             }); //End WebViewClient

            myWebView.loadUrl(url);     
        }

This could probably be done in a smarter way, but I'm new at both Java and Android development...

Is it possible for me to enable the JavaScript for the WebViewClient at all? Removing the WebViewClient solves the problem, but then I can't catch events when the page errors or is finished loading.

I don't know what your exact problem is, but i can enable the JavaScript and a custom WebViewclient without any problem:

WebView vistaWeb = (WebView) findViewById(R.id.webview);
vistaWeb.setWebChromeClient(new MyCustomChromeClient(this));
vistaWeb.setWebViewClient(new MyCustomWebViewClient(this));
vistaWeb.clearCache(true);
vistaWeb.clearHistory();
vistaWeb.getSettings().setJavaScriptEnabled(true);
vistaWeb.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);

The proper way to enable JavaScript is by add the below two lines:

mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);

Even if after adding its not working then try adding the below line.

mWebView.getSettings().setDomStorageEnabled(true);

Now It should work. :)

Rishabh Gupta

Try this to enable javascript

WebView myWebView = (WebView) findViewById(R.id.webView);
myWebView.getSettings().setJavaScriptEnabled(true);
myWebView.setWebViewClient(new WebViewClient());
myWebView.loadUrl(url);

Do "Javascript-URLs" get routed through shouldOverrideUrlLoading? Try checking that and if so, return false for links like that (so that the webview handles the link, not your WebViewClient)

What happened in my case : I was serving local html files and when applying

    web.getSettings().setJavaScriptEnabled(true);
    web.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);

but then my urls stopped working. Solution to make both JS and local href work was to add

    web.getSettings().setAllowFileAccess(true);
    web.getSettings().setAllowFileAccessFromFileURLs(true);

where

    web = (WebView) findViewById(R.id.embedded_web);

Similar to @mdelolmo answer, but in Kotlin:

    webview.setWebChromeClient(WebChromeClient())
    webview.setWebViewClient(WebViewClient())
    webview.clearCache(true)
    webview.clearHistory()
    webview.getSettings().setJavaScriptEnabled(true)
    webview.getSettings().setJavaScriptCanOpenWindowsAutomatically(true)

来源：https://stackoverflow.com/questions/5089578/enabling-general-javascript-in-webviewclient

标签

android

webview

webviewclient